Cangas de Onís is a municipality in northwest Spain. In Cangas de Onís town, the 5-arched Roman Bridge spans the Sella River. Southeast, Picos de Europa National Park is home to trails, limestone formations and the high-altitude Lakes of Covadonga. Its rich birdlife includes golden eagles. At the edge of the park is Covadonga Sanctuary, with its twin spires. Nearby, the sacred cave Santa Cueva lies above a waterfall.